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arXiv · 1910.01787

Large Magnetoelectric Response in Sr2IrO4/SrTiO3 superlattices with non-equivalent interfaces

Xin Liu·Peipei Lu·Mei Wu·Yuanwei Sun·Jingdi Lu·Jing Wang·Dayu Yan·Youguo Shi·Zhiping Yin·Nian Xiang Sun·Peng Gao·Young Sun·Fa Wang·Ce-Wen Nan·Jinxing Zhang
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Abstract

Large magnetoelectric response in thin films is highly desired for high-throughput and high-density microelectronic applications. However, the d0 rule in single-phase compounds usually results in a weak interaction between ferroelectric and magnetic orders; the magnetoelectric coupling via elastic resonance in composites restricts their thin-film integration in broadband. Here, we effectuate a concurrence of ferroelectric-like and antiferromagnetic phase transitions in Sr2IrO4/SrTiO3 superlattices by artificial design periodically non-equivalent interfaces, where a maximum magnetoelectric coefficient of ~980 mV cm-1 Oe-1 can be measured. Evidenced by synchrotron X-ray absorption and electron energy loss spectroscopies, a lopsided electron occupation occurs at the interfacial Ti ions. From perturbative calculations and numerical results, a strong coupling of antiferromagnetism and asymmetric electron occupation mediated by spin-orbit interaction leads to a large bulk magnetoelectric response. This atomic tailoring of the quantum order parameters in 3d and 5d oxides provides an alternative pathway towards strong magnetoelectric effects with thin-film integrations.

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Xin Liu, Peipei Lu, Mei Wu, Yuanwei Sun, Jingdi Lu, Jing Wang, Dayu Yan, Youguo Shi, Zhiping Yin, Nian Xiang Sun, Peng Gao, Young Sun, Fa Wang, Ce-Wen Nan, Jinxing Zhang. 2019-10-04. Large Magnetoelectric Response in Sr2IrO4/SrTiO3 superlattices with non-equivalent interfaces. https://arxiv.org/abs/1910.01787

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